349 (Including references to Who’s Who in the Theatre and Who Was Who in the Theatre) For in-out catheterization to obtain a post-void residual, allowing the bladder to drain completely into a graduated container and measure the volume, then remove the catheter this should be performed shortly after a voluntary void to ensure an accurate post-void residual.Preface. Once placement is confirmed, inflate the catheter balloon with sterile water or saline. Insert a well-lubricated catheter into the urethral meatus with the dominant, sterile-gloved hand, and observe for a spontaneous return of urine to confirm placement in the bladder. The urethral meatus and glans penis for males or perineum for females should undergo prepping with an antiseptic solution using sterile technique. The non-dominant hand should hold the penis at a 90-degree angle toward the ceiling, and for females, the labia should be separated and held to expose the urethral meatus. Perform hand hygiene and place the patient in position of accessibility a female patient should be placed in the frog-leg position, sterile drapes should cover the genitals with the urethral meatus exposed. The male and female anatomy requires different techniques with inserting a urethral catheter, but the overall procedure and sterile technique are similar. Urethral catheterization directly measures the post-void residual and is considered the gold standard for determining post-void residual, although there may be variable volumes present after catheterization, depending on the size and type of catheter used for drainage. There is some evidence that bladder scanners are more accurate than two-dimensional ultrasound imaging. Abdominal ascites appears to cause falsely elevated measurements in some cases. Different bladder scanner machines may have slightly different procedures, but the basics of the technique are similar across devices.īladder scanning is not suitable for use on patients with severe abdominal scars, prolapses of the uterus, or current pregnancy. The process can be repeated to better align the bladder in the center of the display. The button is depressed, initiating the machine's evaluation of the bladder's volume, which is then displayed for the operator to see. The patient lies supine, ultrasound gel is to be placed at the suprapubic area, and the probe is then placed on the gel and directed toward the patient's bladder. It is a non-invasive approach to identifying post-void residual.
The portable bladder ultrasound device (commonly known as a bladder scanner)Ī portable bladder ultrasound device uses ultrasound to specifically measure the three-dimensional volume of urine in the bladder. Although most studies demonstrate high accuracy of post-void residual using transabdominal point-of-care ultrasound or bladder scanners with automated measurement of bladder volume, other recent studies have brought their accuracy into question. ĭata on the accuracy of transabdominal ultrasound for determining post-void residual is mixed. This method is recommended as the standard calculation because it is fast and easy. The bladder is measured at its maximal transverse (width), longitudinal (length) and anterior-posterior (height) diameters. (Note, the prolate ellipsoid formula has multiple acceptable correction factors.) Transvaginal ultrasound appears especially accurate for measuring low bladder volumes.
It measures the bladder’s volume using the ultrasound machine's internal volume calculations or the mathematical equation seen below.
The conventional ultrasound is used to visualize the bladder directly, either transabdominally or transvaginally. Ultrasound (conventional or real-time ultrasound) Measurement of post-void residual immediately after voiding is crucial for accurate measurement, with delays of as little as 10 minutes from bladder emptying to post-void residual measurement potentially causing clinically significant overestimation of post-void residual. Urinary catheterization is the gold standard for measuring the post-void residual. Post-void residual evaluation is by measuring the remaining urine in the bladder shortly after a voluntary void this can be accomplished through ultrasound, bladder scan, or by directly measuring the urine volume drained by a urinary catheter.